Those are exactly the bones to which I'm referring; and no, they aren't too small to feed; raw bones are a healthy, natural part of a cat's diet and, as such, are not "dangerous". Just imagine how small a mouse's bones are, or a baby bird's....
Both the speed as well as the phases of a transition are, mostly, up to the cats. Some cats understand what to do with raw meaty chunks and bones right away, some have a slow start and then a remarkably fast learning curve, some take a very long time to get fully on-board.
The "final" stage of bone-in meals is whatever you plan to feed on a regular basis. I feed chicken wings (minus the drummette), chicken ribs, rabbit ribs and other small rabbit bones.
Hope this is helpful!
AC